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Three species of penguins were studied to examine the speed at which they swim while searching for prey and actually pursuing prey. It was found that Adelie penguins, Pygoscelis adeliae, slowed their speed down to feed, Magellanic penguins, Spheniscus magellanicus, increased their speed, and king penguins, Aptenodytes patagonicus, swam at varying speeds. It is thought that the type of prey being pursued may be relevant in the speed used for capture.

Abstract: Determining the movement of marine animals is logistically difficult and is currently primarily based on VHF and satellite-tracking telemetry, GPS, acoustic telemetry, and geolocation, all of which have substantial limitations in accurately locating the fine-scale movements of these animals. A recent development—that of dead-reckoning—is being increasingly used to examine the fine-scale movement of animals underwater. The advantages and drawbacks of this approach are quite different to those incurred by the other methods. This paper considers the advances that dead-reckoning can bring to the study of the often cryptic movement and behaviour of marine animals at sea. Methods used in determining position via dead-reckoning are presented and consideration is given to results derived from the use of dead-reckoning on cetaceans, pinnipeds, penguins and sea turtles; these are complemented by data on cormorants and albatrosses acquired using GPS systems. Suggestions are made as to how movement data derived from these devices can be analysed using indices that allow interpretation over a large variety of temporal and spatial scales. [Copyright &y& Elsevier]

Abstract: Seven nominally identical samples of Na-free carbonate apatite (CO3Ap) were prepared by reaction of CaHPO4 with ammonium carbonate solution at 70°C over 3 days. They were studied by chemical analysis, Rietveld analysis of powder X-ray diffraction (XRD) data, Ca/P ratio determinations (quantitative phase analysis of CaO, Ca(OH)2 and hydroxyapatite formed after heating to 900°C from Rietveld analysis of XRD data), He pycknometry, 1H, 13C and 31P MAS NMR spectrometry and Fourier transform infrared and Raman spectroscopy. Spectroscopy showed the apatite products were B-type CO3Aps (CO3 2− replacing PO4 3−) and XRD that one sample contained 1.6wt% calcite with a trace in another. Mean results of the six essentially calcite-free samples were: a=9.405(5)Å, c=6.896(2)Å; 11.2wt% CO3; unit cell contents, Ca8.241(PO4)4.344(CO3)1.656(OH)0.139·2.29H2O; mole Ca/P ratio from chemical analyses, 1.897(22) and from powder XRD phase analysis of samples decarbonated at 900°C, 1.892(25). Density determinations indicated that the 2.29mol of H2O were in the unit cell. Rietveld refinements were undertaken without and with explicit modelling of the CO3 2− ion. The latter used constraints to maintain the CO3 2− ion in its known geometry and the total of PO4 3− and CO3 2− ions per unit cell at six. Without the CO3 2− ion in the model, PO4 volume, P–O bond lengths and P occupancy were apparently reduced, consistent with CO3 2− replacing PO4 3− ions. With the CO3 2− ion modelled, the reductions were less and the CO3 2− ion occupied the “sloping” face of the replaced PO4 3− ion in two-fold disorder about the mirror plane. The angle between the normal to the plane of the ion and the c-axis was 34°, close to 35.3°, the equivalent angle for the PO4 3− ion. When modelled, the CO3 2− ion occupancy was 1.81 ions per unit cell, in reasonable agreement with unit cell contents determined chemically (1.66). The OH− ion occupancy was elevated (2.33 ions per unit cell versus 0.14 inferred from the charge balance), which we ascribe to H2O molecules occupying sites in c-axis channels. The Ca/P ratio from occupancies (2.31) was also elevated over that determined chemically (1.90). We attribute this to loss of Ca from Ca sites increasing the apparent anisotropic displacement parameters of remaining Ca atoms, leading to an apparently increased occupancy. [Copyright &y& Elsevier]

Nine samples of Ca-deficient apatite (Ca-def Ap) were prepared from suspensions of CaHPO4 (monetite) at 90°C by raising the pH from ∼4 through release of NH3 produced by the hydrolysis of urea. Products were dried at 100°C for 24 h and studied by chemical analyses, X-ray powder diffraction (XRPD) (and Rietveld analysis of this data), Ca/P ratio determination (quantitative phase analysis of samples after heating to 900°C from Rietveld analysis of XRPD data), scanning electron microscopy, He pycknometry, 1H and 31P MAS NMR spectrometry and Fourier transform infrared and Raman spectroscopy. All samples contained apatite, but three also contained monetite. Infrared and Raman spectroscopy confirmed the presence of HPO42- and absence of carbonate ions in the six monetite-free samples. Mean results for the six samples were: a=9.4320(40), c=6.8751(31) Å; unit cell formula from chemical analysis neglecting protonation of phosphate ion, Ca9.303(50)(PO4)6(OH)0.606(99).1.97(12)H2O; theoretical density 3.10 g cm-3; experimental density (mean for three samples) 3.15 g cm-3; and Ca/P mole ratio from chemical analysis and phase analysis after heating to 900°C, 1.550(8) and 1.550(2), respectively. An earlier assignment of a line at 6 ppm in the 1H NMR spectrum of similar samples to HPO42- ions could not be confirmed; hence no information about the HPO42- ion content could be derived, in disagreement with the previous NMR study. A shoulder at ∼0.9 ppm relative to 85 wt% H3PO4 in the 31P NMR spectrum was assigned to HPO42- ions. Occupancies from the Rietveld structure refinements indicated preferential loss of Ca from Ca2 sites compared with Ca1, but the loss was substantially smaller than expected from chemical analyses. It is suggested that imperfect modelling of the structure in the refinement, particularly disorder associated with the Ca2 site, resulted in errors in Ca2 occupancies. The P–O bonds were slightly shorter than those in stoichiometric hydroxyapatite, rather than longer as might be expected from protonation of phosphate tetrahedra. However, consideration of known acid phosphate structures indicated that it was unlikely that the increase in P–O lengths would be sufficient to be detected. The observed decrease was tentatively assigned to the presence of Ca2+ ion vacancies. [Copyright &y& Elsevier]

X-ray and time of flight neutron diffraction data, FTIR and MAS-NMR spectra, and ICP-AES and carbonate analyses have been collected from a sodium-containing carbonate apatite (CO3 content 12.5(7) wt%). A structural model based on Holly Springs hydroxyapatite without CO32− ions showed an apparent reduction in the PO4 tetrahedral volume which is ascribed to CO32− replacing PO43− ions in the lattice. Four structural models from the literature with the CO32− ion explicitly modelled were fitted to the neutron diffraction data by the Rietveld method.The best fit was obtained with the CO32− ion in disorder between the mirror symmetry related faces of a vacant PO43− site and with the normal to the plane of the CO32− ion at ∼30° to the c-axis. This angle is consistent with results from previous polarised IR measurements on single crystals of francolite (a fluorocarbonate apatite) and human dental enamel. Further refinement of the model revealed a hitherto unknown atom site close to the unit cell origin, (possibly a water molecule). The refined hexagonal unit cell parameters from the neutron diffraction data were a=9.3446(3) A˚ and c=6.9199(4) A˚. [Copyright &y& Elsevier]

Animals are not distributed randomly in space and time because their movement ecology is influenced by a variety of factors. Energy landscapes and the landscape of fear have recently emerged as largely independent paradigms, both reshaping our perspectives and thinking relating to the spatial ecology of animals across heterogeneous landscapes. We argue that these paradigms are not distinct but rather complementary, collectively providing a better mechanistic basis for understanding the spatial ecology and decision-making of wild animals. We discuss the theoretical underpinnings of each paradigm and illuminate their complementary nature through case studies, then integrate these concepts quantitatively by constructing quantitative pathways of movement modulated by energy and fear to elucidate the mechanisms underlying the spatial ecology of wild animals. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanotubes filled with continuous crystalline nanowires of nanometre-scale diameter and micrometre-scale length of the ferromagnetic phase α-Fe were produced with a new chemical vapour deposition method. We report a new two-stage approach, a perturbed-vapour method of synthesis followed by a post-synthesis heat treatment that produces multiwall carbon nanotubes filled with at least 19 micrometre-length nanowires of α-Fe. Previously reported synthesis routes use steady-state conditions to guarantee nanowire continuity but result only in small (less than one-micrometre length) nanowires comprising isolated or mixed phases of either α-Fe, Fe3C, or γ-Fe. Here flower-like clusters of carbon nanotubes continuously filled with α-Fe were produced by perturbation of a laminar ferrocene (Fe(C5H5)2) vapour flow in a conventional horizontal chemical vapour deposition reactor. Single-phase filling was achieved by a post-synthesis annealing at 500°C for 15h in Ar flow. Electron microscopy studies revealed the high quality of the structural integrity of both nanotubes and encapsulated nanowires. These nanostructures possess a high coercivity of 580Oe and a very high saturation magnetization of 189.5emu/g comparable with bulk α-Fe. [Copyright &y& Elsevier]

Abstract: Objectives: Leucite glass-ceramics with fine-grained leucite crystals promote improved mechanical strength and increased translucency. The objectives of the study were to optimize the microstructure of a fine-grained leucite glass-ceramic in order to increase its flexural strength and reliability as measured by its Weibull modulus. Methods: Glass was prepared by a melt-derived method and ground into a powder (M1A). The glass crystallization kinetics were investigated using high temperature XRD and DSC. A series of two-step heat treatments with different nucleation/crystal growth temperatures and holds were carried out to establish the optimized crystallization heat treatment. Glass-ceramics were characterized using XRD, SEM and dilatometry. The glass-ceramic heat treated at the optimized crystallization parameters (M1Aopt) was both sintered (SM1Aopt) and heat extruded (EM1Aopt) into discs and tested using the biaxial flexural strength (BFS) test. Results: High temperature XRD suggested leucite and sanidine crystallization at different temperatures. Optimized crystallization resulted in an even distribution of fine leucite crystals (0.15 (0.09)μm2) in the glassy matrix, with no signs of microcracking. Glass-ceramic M1Aopt showed BFS values of [mean (SD), MPa]: SM1Aopt =252.4 (38.7); and EM1Aopt =245.0 (24.3). Weibull results were: SM1Aopt; m =8.7 (C.I.=7.5–10.1) and EM1Aopt; m =11.9 (C.I.=9.3–15.1). Both experimental groups had a significantly higher BFS and characteristic strength than the IPS Empress Esthetic glass-ceramic, with a higher m value for the EM1Aopt material (p <0.05). Significance: A processable fine-grained leucite glass-ceramic with high flexural strength and improved reliability was the outcome of this study. [Copyright &y& Elsevier]

Abstract: A theoretically valid proxy of energy expenditure is the acceleration of an animal''s mass due to the movement of its body parts. Acceleration can be measured by an accelerometer and recorded onto a data logging device. Relevant studies have usually derived a measure of acceleration from the raw data that represents acceleration purely due to movement of the animal. This is termed ‘overall dynamic body acceleration’ (ODBA) and to date has proved a robust derivation of acceleration for use as an energy expenditure proxy. Acceleration data loggers are generally easy to deploy and the measures recorded appear robust to slight variation in location and orientation. This review discusses important issues concerning the accelerometry technique for estimating energy expenditure and ODBA; deriving ODBA, calibrating ODBA, acceleration logger recording frequencies, scenarios where ODBA is less likely to be valid, and the power in recording acceleration and heart rate together. While present evidence suggests that ODBA may not quantify energy expenditure during diving by birds and mammals, several recent studies have assessed changes in mechanical work in such species qualitatively through variation in ODBA during periods of submergence. The use of ODBA in field metabolic studies is likely to continue growing, supported by its relative ease of use and range of applications. [Copyright &y& Elsevier]

Highlights • New patented formulation of leucite glass-ceramics (OLG-C), with high BFS and SBS. • Novel leucite G-C with reduced flaw size and similar sandblasted BFS to IPS e.max®. • Resin bonding increased BFS for all G-Cs, with 24.6% increase for IPS e.max®. • OLG-C useful for minimally invasive, aesthetic and fracture resistant restorations. Abstract Objectives To process novel leucite glass-ceramics and test the effects of surface treatment and resin bonding on the biaxial flexural strength (BFS) and shear bond strength (SBS). Methods Alumino–silicate glasses were ball-milled, and heat treated to form leucite glass-ceramics (LG-C, OLG-C), then sintered into ingots. Ingots were heat extruded into a refractory mould to form disc specimens (1.3 × 14 mm diameter). IPS e.max® was used as a commercial comparison. Glass-ceramic test groups were sandblasted (Groups. 1, 4, 6), sandblasted, etched and adhesively bonded (Groups. 2, 5, 7) or lapped, etched and adhesively bonded (Groups. 3, 8). Specimens were adhesively bonded with Monobond S, followed by the application of Variolink II® cement and light curing. BFS testing was at 1 mm/min and SBS testing at 0.5 mm/min. Samples were characterised using XRD, SEM and profilometry. Results XRD confirmed tetragonal leucite in LG-C/OLG-C and lithium disilicate/lithium orthophosphate in IPS e.max®. Mean BFS (MPa (SD)) were: Gp1 LG-C; 193.1 (13.9), Gp2 LG-C; 217.7 (23.0), Gp3 LG-C; 273.6 (26.7), Gp4 OLG-C; 255.9 (31); Gp5 OLG-C; 288.6 (37.4), Gp6 IPS e.max®; 258.6 (20.7), Gp7 IPS e.max®; 322.3 (23.4) and Gp8 IPS e.max®; 416.4 (52.6). The Median SBS (MPa) were Gp1 LG-C; 14.2, Gp2 LG-C (10 s etch); 10.6 and Gp3 IPS e.max®; 10.8. Mean surface roughness was 5–5.1 μm (IPS e.max®) and 2.6 μm (LG-C). Significance Novel leucite glass-ceramics with reduced flaw size and fine microstructures produced enhanced BFS and SBS by resin bonding. These properties may be useful for the fabrication of minimally invasive aesthetic and fracture resistant restorations. [ABSTRACT FROM AUTHOR]

Bi 1- x Sm x FeO 3 ( x  = 0.15–0.18) ceramics with high density were produced using spark plasma sintering. The effects of composition, synthesis conditions and temperature on the phase evolution were studied, using XRD, TEM and dielectric spectroscopy. The coexistence of the ferroelectric R3c , antiferroelectric Pnam and paraelectric Pnma phases was revealed, with relative phase fractions affected by both calcination conditions and Sm concentration. Experiments on powdered samples calcined at different temperatures up to 950 °C suggest higher calcination temperatures promote Sm diffusion, allowing samples to reach compositional homogeneity. The structural transitions from the Pnam and R 3 c phases to the Pnma phase were comprehensively investigated, with phase transition temperatures clearly identified. The dielectric permittivity, electrical resistivity and breakdown strength were increased upon Sm-substitution, while ferroelectric switching was suppressed. The polarization-electric field loop became increasingly narrow with increasing Sm-content, but double hysteresis loops, which may reflect a reversible antiferroelectric to ferroelectric transformation, were not observed. [ABSTRACT FROM AUTHOR]

• First study on the effects of air temperature on epigenetic age acceleration. • Medium-term exposures to high temperatures are associated with increased HorvathAA, HannumAA, GrimAA, and SkinBloodAA. • Long-term exposures to high temperatures are associated with increased HorvathAA, HannumAA, PhenoAA, GrimAA, and SkinBloodAA. • More pronounced associations between air temperature and epigenetic age acceleration are observed among women and people with obesity or diabetes. Climate change poses a serious threat to human health worldwide, while aging populations increase. However, no study has ever investigated the effects of air temperature on epigenetic age acceleration. This study involved 1,725 and 1,877 participants from the population-based KORA F4 (2006–2008) and follow-up FF4 (2013–2014) studies, respectively, conducted in Augsburg, Germany. The difference between epigenetic age and chronological age was referred to as epigenetic age acceleration and reflected by Horvath's epigenetic age acceleration (HorvathAA), Hannum's epigenetic age acceleration (HannumAA), PhenoAge acceleration (PhenoAA), GrimAge acceleration (GrimAA), and Epigenetic Skin and Blood Age acceleration (SkinBloodAA). Daily air temperature was estimated using hybrid spatiotemporal regression-based models. To explore the medium- and long-term effects of air temperature modeled in time and space on epigenetic age acceleration, we applied generalized estimating equations (GEE) with distributed lag non-linear models, and GEE, respectively. We found that high temperature exposure based on the 8-week moving average air temperature (97.5th percentile of temperature compared to median temperature) was associated with increased HorvathAA, HannumAA, GrimAA, and SkinBloodAA: 1.83 (95% CI: 0.29–3.37), 11.71 (95% CI: 8.91–14.50), 2.26 (95% CI: 1.03–3.50), and 5.02 (95% CI: 3.42–6.63) years, respectively. Additionally, we found consistent results with high temperature exposure based on the 4-week moving average air temperature was associated with increased HannumAA, GrimAA, and SkinBloodAA: 9.18 (95% CI: 6.60–11.76), 1.78 (95% CI: 0.66–2.90), and 4.07 (95% CI: 2.56–5.57) years, respectively. For the spatial variation in annual average temperature, a 1 °C increase was associated with an increase in all five measures of epigenetic age acceleration (HorvathAA: 0.41 [95% CI: 0.24–0.57], HannumAA: 2.24 [95% CI: 1.95–2.53], PhenoAA: 0.32 [95% CI: 0.05–0.60], GrimAA: 0.24 [95%: 0.11–0.37], and SkinBloodAA: 1.17 [95% CI: 1.00–1.35] years). In conclusion, our results provide first evidence that medium- and long-term exposures to high air temperature affect increases in epigenetic age acceleration. [ABSTRACT FROM AUTHOR]

Highly aligned poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) films were processed using a scalable one-step melt extrusion processing route. Crystalline structure and orientation were optimized by controlling the melt extrusion conditions. XRD patterns suggested the nearly perfect alignment of the c-axis (polymer chain direction) along the extrusion direction in the optimized as-extruded films. SEM analysis confirmed the morphology of the crystalline phase, showing edge-on lamellae stacked perpendicular to the extrusion direction. DSC data indicated high crystallinity and well-ordered ferroelectric structure of the extruded films. The FTIR spectroscopy proved strong intermolecular dipole-dipole interaction in the extruded films. Accordingly, the optimized as-extruded PVDF-TrFE films exhibit a coercive field of 24 kV/mm, half of the commonly reported values for bulk films (∼50 kV/mm) and a remnant polarization of 0.078 C/m 2 which further increased to 0.099 C/m 2 after annealing. This value is close to the theoretical limit (0.102 C/m 2 ) assuming perfect in-plane c-axis orientation and 100% crystallinity. [ABSTRACT FROM AUTHOR]

Abstract: Numerous methods are currently available to track animal movements. However, only one of these, dead-reckoning, has the capacity to provide continuous data for animal movements over fine scales. Dead-reckoning has been applied almost exclusively in the study of marine species, in part due to the difficulty of accurately measuring the speed of terrestrial species. In the present study we evaluate the use of accelerometers and a metric known as overall dynamic body acceleration (ODBA) as a proxy for the measurement of speed for use in dead-reckoning. Data were collated from previous studies, for 10 species locomoting on a treadmill and their ODBA measured by an attached data logger. All species except one showed a highly significant linear relationship between speed and ODBA; however, there was appreciable inter- and intra-specific variance in this relationship. ODBA was then used to estimate speed in a simple trial run of a dead-reckoning track. Estimating distance travelled using speed derived from prior calibration for ODBA resulted in appreciable errors. We describe a method by which these errors can be minimised, by periodic ground-truthing (e.g., by GPS or VHF telemetry) of the dead-reckoned track and adjusting the relationship between speed and ODBA until actual known positions and dead-reckoned positions accord. [Copyright &y& Elsevier]

Abstract: An important element in the measurement of energy budgets of free-living animals is the estimation of energy costs during locomotion. Using humans as a particularly tractable model species, we conducted treadmill experiments to test the validity of tri-axial accelerometry loggers, designed for use with animals in the field, to estimate rate of oxygen consumption (O2: an indirect measure of metabolic rate) and speed during locomotion. The predictive power of overall dynamic body acceleration (ODBA) obtained from loggers attached to different parts of the body was compared to that of heart rate (f H). When subject identity was included in the statistical analysis, ODBA was a good, though slightly poorer, predictor of O2 and speed during locomotion on the flat (mean of two-part regressions: R 2=0.91 and 0.91, from a logger placed on the neck) and O2 during gradient walking (single regression: R 2=0.77 from a logger placed on the upper back) than was f H (R 2=0.96, 0.94, 0.86, respectively). For locomotion on the flat, ODBA was still a good predictor when subject identity was replaced by subject mass and height (morphometrics typically obtainable from animals in the field; R 2=0.92 and 0.89) and a slightly better overall predictor than f H (R 2=0.92 and 0.85). For gradient walking, ODBA predicted O2 more accurately than before (R 2=0.83) and considerably better than did f H (R 2=0.77). ODBA and f H combined were the most powerful predictor of O2 and speed during locomotion. However, ODBA alone appears to be a good predictor and suitable for use in the field in particular, given that accelerometry traces also provide information on the timing, frequency and duration of locomotion events, and also the gait being used. [Copyright &y& Elsevier]

Objectives To evaluate the effects of spark plasma sintering (SPS) on the microstructure of lithium disilicate glass-ceramics. Methods IPS e.max CAD glass-ceramic samples were processed using spark plasma sintering (SPS) and conventionally sintered (CS) as a comparison. Specimens were sintered at varying temperatures (T1: 840 °C, T2: 820 °C, T3: 800 °C), heating rates (HR1: 150 °C/min, HR2: 300 °C/min, HR3: 500 °C/min) and pressures (P1: 15 MPa, P2: 50 MPa, P3: 70 MPa). IPS e.max Press glass powder samples were densified at 750 and 800 °C (50 or 200 MPa pressure). Samples were characterized using XRD, HTXRD, and SEM and quantitative image analysis. Results There was a significant increase in median crystal size (MCS) between the CS and the SPS T1 groups. A statistical difference ( p > 0.05) in MCS between SPS T1 and SPS T2 groups was observed. The SPS HR3 sample produced a smaller MCS than the CS, SPS HR1 and HR2 groups ( p < 0.05). The SPS P3 sample had a reduction in MCS compared with the CS group ( p < 0.05). XRD of the SPS samples revealed major lithium disilicate/lithium metasilicate phases and minor lithium orthophosphate and cristobalite/quartz phases. Densified IPS e.max Press glass samples resulted in fine fibrils or graduated lithium disilicate crystals. Significance The effects of SPS were used to refine the microstructure of IPS e.max CAD lithium disilicate glass-ceramics. Densification by SPS of IPS e.max Press glass resulted in textured and fine nano-crystalline microstructures. SPS generated glass-ceramic microstructures may have unique properties and could be useful in the production of CAD/CAM materials for dentistry. [ABSTRACT FROM AUTHOR]